System of distribution by secondary batteries



(No Model.)

G. B. PRESCOTT, Jr.

SYSTEM OF DISTRIBUTION BY SECONDARY BATTERIES.

No. 402,191. Patented Apr. 30, 1889.

n. ruins, Phmc-Um nbM r, Wiminrton. n. C.

UNITED STATES PATENT OFFICE.

GEORGE Ii. PRESCOITT, JR, OF NEIYARK, NE\\' JERSEY, ASSIGNOR TO TIIE EIIEWIRICAL ACC I MI Ih YIOR OMPl-XNY, OF XEIY YORK.

SYSTEM OF DISTRIBUTION BY SECONDARY BATTERIES.

SPECIFICATION forming part of Letters Patent No. 402,191, dated April 30, 1889.

Application filed February 15, 1889, Serial No' 299,988. (No modeld To (LU wit H0 7"! may (OILFG/lo Be it known that I, GEORGE l3. Pinisco'rir, Jr, a citizen. of the United States, and a resident of Newark, in the county of Essex and E State of New Jersey, have invented certain new and useful Improvements in the Regulation of .Eleetro-Motive Force in Distributing Systems Employing Secondary Batteries, oli' which the following is a specification.

My invention is an improvement in the regulation oi. elcctro motive force .in. distributing systems employing secondary batteries.

The invention contemplates the use of a primary generator of electricity, located at a central station,and one or more sub-stations,

at each. of which there located a secondary F battery and a working-circuit to be supplied thereby. The main and sub stations are to be connected by two or more main leads, called the charging-circuit. In this arrangement of apparatus, when the dynamo is being operated to charge the battery at any given. station and the working-eircuit is 1 simultaneously supplied from the l. attery, it happens that the excessive electro-motive force necessarily employed to charge the battery is manifest and is injuriously active in the working-circuit. My invention is dc signed to obviate this diliiculty. I connect the workingcireuit at the sub-station with the central station. by a circuit composed of two conductors. Located in circuit with these conductors at the central station. is an indicating-instrument. In a se )aratc circuit at the sub-station. I place an elcctro-magnetcontrolling a switch for introducing or withdrawing successively a se ies oli' electrolytic cells yielding an. clcctro-motive ll: rce the reverse of that due to the main. battery. In the short circuit normally existing round. these cells there is a low artificialmsistance elf considerable capacity useful in preventingthe rapid discharge of these cells. I provide a switch at the central station for completing a third. circuit between. the central station and a substation. and for varying the current flowing therein. This third cireu it practically electrically independent of the charging-circuit and ot the indicator-cireuit, but is composed of parts of both and includes the electr0-1nagnot controlling the switch at the sub-station lYhen the indicator at the central station 1 shows a variation from the normal electro' i motive force in. the workin g-circuit at the suit station, I vary the resistance in the third cir- 5 cuit, thus operating the switch at the substation to change the number of electrolytic cells in opposition to the electro-motive force of the battery at the sub-station, and to thus vary the electro-motive force at the lamp-terminals.

The accompanying drawing illustrates my invention.

D is a dynamo located at a central point or station. It is connected by main leads 9 1O with sub-stations X and Y. This circuit I call the charging-circuit. Stations X and. i Y are similar, and I will. describe my inven 5 tion by reference to one station only,

At station X there is a seriesot cells oisec-' ondary battery B, a switch, s, for including and excluding it with respect to the charging l circuit, and a rcgulating-switch,[orvarying the number of cells in. circuit.

ois a working-oircuit containing lamps l, and there are a series of secondary-battery cell normally cut out of circuit by a switch, which when operated breaks the circuit round each cell. successively, thus in troducing it into the working-circuit. The series of tap-wires 2 l 5 6 connect points between each pair ol' cells with a series of fixed mercury-cups, n. In the circuit elf tap-wires 33, l, and there are artificial. resistances to provide against short-circuiting any cell, and at 7 there is a similar resistance to provide against shortcircuiting the entire series of cells during the time they are cut out of circnit H. ries of electrical. contacts-ono for each mercury-cup, m isa solenoid elcctro-magnet. Its core is connected to bar it Two conductors, 11) 20, are joined to opposite sides of the working-circuit uat points 7O 71., and these are united through an indicator, 1', at the central station. The indicator 1' is practically a voltmeter, its needle standing at a central point when the elcctro-motive force in circuit 1/; is at the normal, and. moving in one direction or the other with a rise or fall of electro-motive force, as the ca e may be, In one side of this circuit-that is, in conductor ill-the solenoid IOO on at the sub-station is placed. At the central station there is a branch circuit, 21, for connecting indicator-circuit 19 with main lead 9, to form a third and practically independent circuit. In the branch circuit 21 is avariable artificial resistance, R, and an ammeter, Cb.

We will assume that the battery is operating to supply the lamps in the working-circuit w, and that indicator t' shows a normal electromotive force at the points 70 71. The dynamo now begins the operation of charging battery B, and the indicator 1' shows a rise of electromotive force at points 70 71. The central-station attendant notices this rise of electro-motive force and proceeds to operate the circuitchanger b. It will be seen that magnet m is in a third and separate circuit composed of conductor 21 9 D 10, through station Y 9 to at X, to point '70 19 m, ammeter a, and resistance R. By moving arm rto the left the artificial resistance in this circuit is decreased and the strength of current is increased. The core of m is drawn down until the short circuit through the mercury-cup and tap-wires 5 and 6 is broken. This admits cell 0 into the working-circuit 10. It opposes its electro-motive force of, say, twovolts to that of the battery.

This is immediately evident on the indicatinginstrument 2'. If it is insufficient to reduce the electro-motive force to its normal, the strength of current flowing in the described third cir cuit is still further increased by decreasing resistance at R until a second cell, 0 is included in the Working-circuit w,'reversed with respect to battery B, and this operation is continued until a sufficient counter electro-motive force is operative in the working-circuit to neutralize the excess in electro-motive force appearing at the lamp-terminals. It is to be noticed that when cell c is introduced into working-circuit w the artificial resistance in the tap-wire 5 and the artificial resistance at 7 are also included in series, and serve to cause a slight additional drop in electro motive force to that produced by the counter electromotive force of cell 0 but this resistance is mainly to avoid an excessively rapid discharge When the counter-electro-motive-force cells are removed from the working-circuit. So, too, when cell c is added to circuit 20, the resistances 4 and 7 are included.

What I claim, and desire to secure by Letters Patent, is-

1. The combination of a primary generator of electricity located at a main station, a charging-circuit, a secondary battery located at a sub-station, a working-circuit therefor, one or more cells yielding a counter electromotive force to be introduced and withdrawn with respect to the working-circuit, a switch or circuit-changer controlling the position of said cells, an electro-magnet for operating the switch, and a separate circuit connecting the main and sub stations, including the coils of said magnet.

2. The combination of a primary generator of electricity located at one station, a secondary battery located at a second station, a

coils in an electrical circuit uniting both stations, substantially as described.

3. The combination of a primary generator of electricity located at one station, a secondary battery located at a second station, a charging-circuit uniting said stations, a working-circuit for the battery, one or more cells yielding a counter electro motive force to be inserted and withdrawn with respect to the working-circuit, a circuit connecting points in the working-circuit at one station with an indicator at the other station, an electro-magnetic switch at the sub-station controlling the counterelectro-motive-force cells, and an electrically-independent circuit uniting both stations and controlling the electro-magnetic switch, substantially as described.

4. The combination of a primary generator of electricity located at one station, a secondary battery located at a second station, a

charging-circuit uniting said stations, a working-circuit for the battery at said second station, a series of cells yielding a counter electro-motive force, a switch or circuit-changer for varying the connections of said cells with respect to the working-circuit, an electro-magnet controlling said switch, a separate circuit containing the coils of said magnet, and a third circuit connecting points in the working-circuit with an indicator located at the first station, substantially as described.

5. The combination of a primary generator of electricity located at a main station, a secondary battery located at a sub-station, a charging-circuit uniting both stations, a working-circuit for the secondary battery, a series of artificial resistances and one or more cells yielding a counter electro-motive force to be inserted and withdrawn with respect to the working-circuit, a switch or circuit-changer controlling the position of said cells, an electro-magnet for operating the switch, and a separate circuit connecting the main and sub stations, including the coils of said magnet.

6. The combination of asecondarybattery, a working-circuit therefor, a series of cells yielding a counter electro-motive force, and a switch or circuit-changer for introducing one cell after another between the battery and working-circuit, substantially as described.

7. The combination of a secondarybattery, a working-circuit therefor, a series of cells yielding a counter electro-motive force, located in theworking-circuit, a circuit containing an artificial resistance around each cell, and a switch or circuitrchanger operating to break the circuit of each cell successively, substantially as described.

8. The combination of a SeCOllilflly battery, in g such circuits successively to introduce said a working-eircuit therefor, a series of cells cells and resistance with respect to the work- 10 yielding a counter electro-lnotive force, 10- ing-cireuit, substantially as described.

cated in the \\'orki11 '-circnit a sectional artii i i y r ficial resistance fOl ilCll celis included in cir- PRESQ 0 cuit therewith, and a switch or cireuit-cha11ger normally completing a circuit round each cell, including a resistance and means for break- Witnesses;

V. E. SGHAUMBURG, F. D. L. WALKER. 

